| Description | Products contentProducts IntroductionThe 2.5×TFS Master Mixture is a premixed system for all types of multiplexed PCRs. It contains DNA polymerase, PCR Buffer, dNTPs, Mg2+, stabilizers and enhancers at a concentration of 2.5×, which makes it easy and fast to use.The DNA polymerase Products contentProducts IntroductionThe 2.5×TFS Master Mixture is a premixed system for all types of multiplexed PCRs. It contains DNA polymerase, PCR Buffer, dNTPs, Mg2+, stabilizers and enhancers at a concentration of 2.5×, which makes it easy and fast to use.The DNA polymerase contained in the 2.5×TFS Master Mixture is a genetically engineered recombinant enzyme with 5'→3' DNA polymerase activity and no 5'→3' exonuclease activity; it is a new antibody-modified hot-start enzyme that can effectively reduce non-specific amplification caused by non-specific binding of primer and template or primer dimerization at room temperature. The DNA polymerase is modified by a new type of antibody, which is an antibody-modified hot-start enzyme, and can effectively reduce the non-specific amplification caused by the non-specific binding of primers and templates or primer dimerization at room temperature, and at the same time, it has the excellent features of short activation time, strong amplification ability, high sensitivity, good stability, etc. The unique PCR buffer system and the hot-start enzyme are suitable for the PCR. The unique combination of PCR buffer system and hot starter enzyme significantly improves the PCR amplification efficiency, sensitivity and inhibitor tolerance.The product has a wide range of applications, not only for general and dye-based real-time fluorescence PCR, but also for forensic multiple STR amplification reaction, which can be used in forensic analysis, parentage identification and scientific research and other human genetic identification. caveat1. Before use, please mix the product gently by turning it up and down after it is completely melted and centrifuged briefly.2. Avoid repeated freezing and thawing of the product, which may degrade its performance. This product can be stored at -20℃ for a long time. UsageThe following examples are STR reaction systems and conditions, which should be improved and optimized according to the specific use, template, primer structure, target fragment size and amplification effect.PCR reaction systemExtract the DNA amplification reaction system:Blood Card Direct Expansion Reaction System:Attention:1) When designing the primers, the difference between the Tm of each primer should be minimized, and the difference should be controlled within 5℃ as far as possible. If the amplification efficiency is not high, the concentration of primers can be increased; if non-specific amplification occurs, the concentration of primers can be decreased to optimize the reaction system. For optimal amplification, it is recommended that the primer mixture be vortexed for 10 s and centrifuged briefly before use.(2) The amount of DNA template is usually 0.1 ng-1 ng of human genomic DNA as a reference, and the amount of template input can be adjusted according to the amplification effect to determine the optimal amount of template to use.3) Human genome contamination should be avoided during the operation, and a set of negative control (no DNA) is recommended for the experiment.2. PCR reaction conditionsAttention:1) Two-step PCR reaction program is recommended. If you can not get good results due to low Tm value of the primers or large difference in Tm value between primers, you can try to use three-step PCR amplification, the annealing temperature should be set in the range of 55℃-65℃ as a reference (the annealing temperature is usually 5℃ lower than the Tm value), and the extension temperature should be set at 72℃.(2) When good amplification results are not obtained, the annealing and extension time can be appropriately prolonged to 120 s-150 s. The annealing and extension time can be extended to 120 s-150 s. (3) When the PCR product detection appears to be incomplete plus A, the final extension time can be appropriately extended to 30-40 min. 4) The number of cycles can be set according to the downstream application of the amplified product, if the number of cycles is too small, the amplification is insufficient, the recommended number of cycles is 28-31 cycles.5) Blood card direct amplification can be based on the actual amplification effect to increase the 72 ℃ lysis step to improve the amplification efficiency.6) When using the ABI 9700 Thermal Cycler, perform amplification in MAX mode.7) PCR products can be stored at 2-8°C for short-term storage or at -20°C for long-term storage.Attention:(1) Usually, a primer concentration of 0.2 M can give better results, and 0.1-1.0 µM can be used as a reference for setting the range. If the amplification efficiency is not high, the concentration of primer can be increased; if non-specific reaction occurs, the concentration of primer can be decreased to optimize the reaction system.(2) The final concentration of the probe used is related to the fluorescence quantitative PCR instrument used, the type of probe, and the type of fluorescent labeling substance, please refer to the manual of the instrument or the specific requirements for the use of each fluorescent probe to adjust the concentration.3) Usually the amount of DNA template is 10-100 ng of genomic DNA or 1-10 ng of cDNA as a reference, as templates of different speciesThe number of copies of the target gene contained in them varies, and a gradient dilution of the template can be performed to determine the optimal amount of template to use. PCR reaction conditions :(1) The enzyme used in this product is activated by pre-denaturation at 95°C for 30 s. Most of the templates can be deconvoluted well under this condition. Under this condition, most of the templates can be well unchained. For templates with high GC content and complex secondary structure, the pre-denaturation time can be extended to 1 minute, so that the starting template can be fully unchained, and if the high temperature treatment time is too long, it will affect the activity of the enzyme; for simple templates, pre-denaturation can also be used for 20 s, and the optimal pre-denaturation time can be determined according to the template situation.(2) It is recommended to use two-step PCR program, the annealing temperature should be 58-64℃ as the reference range, and the annealing temperature can be increased in case of non-specific reaction. If you can't get good results due to the use of primers with low Tm value, you can try three-step PCR amplification, and the annealing temperature should be set in the range of 56℃-64℃ as a reference. The annealing and extension times for several common instruments are shown in the following table: 20 s for Roche, BioRad, Agilent, Hongshi, Dongshenglong, etc. 30 s for ABI 7000/7300/7500. The annealing/extension times can be set according to the different types of instruments and templates, please follow the instructions of the instruments. The annealing/extension time can be set according to different models of instruments and templates, please follow the instruction manual of the instrument... Read More | Inquire | Amyloid β-Protein Fragment 25-35 (Aβ25-35) is derived from the amyloid-β protein.amyloid-β protein, which is mapped to human chromosome 21q21.Aβ25-35 lacks the N-terminal domain and the metal binding site and is majorly generated by proteolytic cleavage of Aβ(1−40Amyloid β-Protein Fragment 25-35 (Aβ25-35) is derived from the amyloid-β protein.amyloid-β protein, which is mapped to human chromosome 21q21.Aβ25-35 lacks the N-terminal domain and the metal binding site and is majorly generated by proteolytic cleavage of Aβ(1−40) peptides. It has a β-sheet and β-turn structure. Amino Acid Sequence Gly-Ser-Asn-Lys-Gly-Ala-Ile-Ile-Gly-Leu-MetFunctional domain of Aβ required for both neurotrophic and neurotoxic effects... Read More | Biochemical Test:SDS-PAGE (purity > 80%); Western blot with patient sample.Calculated Isoelectric Point:pH 6.10 | Protein Purity>90 % by SDS PAGEExtinction CoeffA280 nm = 0.725 at 1.0 mg/mL for pure C1s-C1INH ComplexMolecular Weight196,000 Da (1 chain)General DescriptionThe product C1s-C1INH Complex is made by interacting purified protease inhibitor C1-INH with purified C1s enzyme followed by purification. Protein Purity>90 % by SDS PAGEExtinction CoeffA280 nm = 0.725 at 1.0 mg/mL for pure C1s-C1INH ComplexMolecular Weight196,000 Da (1 chain)General DescriptionThe product C1s-C1INH Complex is made by interacting purified protease inhibitor C1-INH with purified C1s enzyme followed by purification. The protease inhibitor C1-INH prevents the spontaneous activation of complement and limits consumption of C2 and C4 by rapidly inactivating C1r, C1s and MASP2. It is the only plasma serine protease inhibitor (Serpin) capable of interacting with and inhibiting activated C1. C1-INH interacts with the catalytic sites of both C1r and C1s. The interaction with activated C1r and C1s is covalent resulting in complexes which are stable to SDS. C1s and C1r enzymes, however, are irreversibly inactivated by binding to C1-INH. C1s-C1INH is a very stable complex that remains intact even when subjected to freeze/thaw cycles with almost no loss of the complex form.Physical Characteristics & StructureThe C1s enzyme-C1INH complex is composed of two disulfide linked chains from C1s enzyme (A chain 58,000 Da and B chain 28,000 Da) and one covalently linked chain from C1-INH (75,000 Da).SDS-PAGE analysis of the C1s-C1INH complex shows a single band of about 161,000 Da under nonreducing conditions. Under reducing conditions, the C1s-C1INH complex exhibits two bands: A 58,000 Da band corresponding to the A chain of C1s enzyme and a second 103,000 Da band resulting from C1INH (75,000 Da) covalently bond to the B chain (28,000 Da) of C1s enzyme.RegulationActivated C1s is controlled by C1-INH. C1s enzyme and C1-INH form a covalent complex that is resistant to separation on SDS gels. During complement activation C1 complex is rapidly activated by binding to immune complexes. The resulting activated C1s and C1r are rapidly inactivated by interaction with C1-INH (Ziccardi, R.J. (1982)). Binding to immune complexes is fast (10-20 sec) and activation of the bound C1 complex takes several minutes, but C1-INH has also been shown to be fast and no active C1r or C1s remain 4 min after addition of immune complexes to plasma (Ross, G.D. (1986); Ziccardi,R.J. (1981)). The binding of C1-INH to activated C1 releases both C1r and C1s from the complex leaving C1q bound to the immune complex. The released complexes contain four molecules: C1-INH-C1r-C1s-C1-INH. The reaction of C1 esterase inhibitor with activated C1 is very fast with the estimated half-life of C1r and C1s being approximately 15 seconds in serum. In fact, at serum concentrations of C1- INH little or no additional C4 or C2 activation occurs 3 min after immune complexes are added because all the C1r and C1s molecules have been inactivated and removed from the C1q which remains bound to the immune complex (Ross, G.D. (1986); Morley, B.J. and Walport, M.J. (2000); Rother, K., et al. (1998); Ziccardi, R.J. (1982a and 1982b); Morgan, B.P. (1990)). The interaction of purified C1s enzyme and C1-INH is slower.FunctionSee General Description and Regulation above.ApplicationsC1s-C1INH complex can be used in studies designed for developing and identifying inhibitors of C1s-C1INH complex formation and thus lead to the possible development of therapeutics for inhibiting complement activation via the classical pathway.GeneticsThe EMBL/Genbank cDNA accession number for C1s is J04080. The gene for C1s is located on chromosome 12p13. The EMBL/Genbank cDNA accession numbers for C1-INH are M13656 and X54486 (human) and Y10386 (mouse). The gene for C1-INH is located on chromosome 11p11.2-13. DeficienciesC1s deficient patients are prone to systemic lupus erythematosus (SLE) and recurrent pyogenic infections (Rother, K., et al. (1998)). They lack classical pathway function. The genetic disorder hereditary angioedema (HAE) is caused by a partial deficiency of C1-INH. Patients with HAE have low functional C1-INH levels in blood and have recurrent episodes of systemic or localized edema.DiseasesSee section titled Deficiencies above. Precautions/Toxicity/HazardsThis protein is purified from human serum and therefore precautions appropriate for handling any blood-derived product must be used even though the source was shown by certified tests to be negative for HBsAg, HTLV-I/II, STS, and for antibodies to HCV, HIV-1 and HIV-II.ReferencesZiccardi, RJ. (1982) A new role for C-1-inhibitor in homeostasis: control of activation of the first component of human complement. J. Immunol. 128:2505-2508.Ross, G.D. (1986) Immunobiology of the Complement System. (ISBN 0-12-5976402) Academic Press, Orlando.Ziccardi, R.J. (1981) Activation of the early components of the classical complement pathway under physiologic conditions. J. Immunol. 126:1769-1773.Morley, B.J. and Walport, M.J. (2000) The Complement Facts Book. (ISBN 0127333606) Academic Press, London.Rother, K., Till, G.O., and Hӓnsch, G.M. (1998) The Complement System. (ISBN 3-540- 61894-5) Springer-Verlag, Heidelberg.Ziccardi, R.J. (1982a) Spontaneous activation of the first component of human complement (C1) by an intramolecular autocatalytic mechanism. J. Immunol. 128:2500- 2504.Ziccardi, RJ. (1982b) A new role for C-1-inhibitor in homeostasis: control of activation of the first component of human complement. J. Immunol. 128:2505-2508. Morgan, B.P. (1990) Complement Clinical Aspects and Relevance to Disease. (ISBN 0- 12-506955-3) Academic Press, London... Read More |